1. Field of the Invention
The invention relates to a bearing or roller bearing with data sensing of the type comprising a stationary element carrying a data sensor device and a rotating element carrying a magnet.
2. Background of the Related Art
The development of automatic operations now requires the exact measurement of the speed and angle of rotation of mechanical elements. A device is known from French published Patent Application FR-A-No. 2 565 045 for the detection of the anglular position of a rotor. It consists of a disk mounted coaxially on a revolving shaft and having a radial face to which are fastened permanent magnets of alternatingly reversed polarity for producing a magnetic field, and Hall-effect proximity sensors placed in the vicinity of the radial face and carried by a portion of the stator coaxial with the revolving shaft, the sensors being angularly adjustable and able to detect the axial component of said field.
French published Patent Application FR-A-No. 2 568 377 similarly describes a rotating machine speed sensor.
When such a device is mounted in a rotating machine, however, its operation can be disturbed by magnetic field induced in the stator or in the rotor.
The lack of precision in assembling the machine, coupled with the ability of the magnets to produce relatively strong fields (several hundred gauss), at times causes the magnet to disturb the environment or pick up metal particles.
The integration of the elements directly into a rotating machine would lead to products usable in a broad temperature range (-40.degree. to +150.degree. C.) which would eliminate the need for numerous traditional components.